• Tribology and Lubricants
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• v.11 no.5
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• pp.136-143
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• 1995

The effect of additive chemistry on the serface fatigue of gears was investigated using the FZG gear tester and fluids based on an API GL-5 grade oil. Surface fatigue lives were determined as a function of load and additive chemistry. At 1.52 GPa, the removal of the primary extreme pressure additive (EP) from the fully formulated gear oil decreased the fatigue life of gears slightly (4%), however, the removal of the primary antiwear additive (AW) decreased the fatigue life of gears significantly (83%). At 1.86 GPa, the removal of the EP additive from the fully formulated gear oil decresed the gear fatigue life 27%, however, the removal of the primary AW additive decreased the fatigue life of gears significantly (75%). Micropitting was the dominant surface morphology in the dedendum of gears tested With two oils at load stage: one using the complete additive package, and a second where the EP additive has been removed. However, spalling is the primary failure mode of gears tested without an AW additive independent of whether an EP agent was present. Surface analysis of pinion gears showed the formation of a mixed phosphate/phosphite-oxide layer on the surface of gears tested with fluids containing an AW. Formation of this layer seems to be key to long fatigue life.

• Hwankyungkyoyuk
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• v.2 no.1
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• pp.5-33
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• 1991

The purpose of the study was to investigate attitudes toward to, values and expectations of environmental education of Korean students and teachers and to provide basic data and reference materials needed to development of environmental education curricula for primary and secondary schools. A review of the related literature, a series of conferences with teachers and specialists in environmental education and environmental sciences. and questionnaire survey were methods employed in this study. Survey question were developed to explore attitude and responses of primary and secondary school students and teachers on various types of issues and problems of environmental education at personal level as well as on their future prospects attitudes values and expectations with which had been dealt in this study were categorized into personal feeling on environmental issues and problems at both national and regional levels issues and problems of current environmental education pre service and in service training of teachers for environmental education instruction and so on. The sample population for the survey was selected by using the stratified cluster and random sampling techniques with respect to regional area, school level, sex and grade, The subjects used in this study were 1,633 students and 385 teachers of primary and secondary schools across the country. The results of the survey were summed up and recommendations to be considered in the revision of sixth national curricula for primary and secondary schools were also suggested.

• Journal of Korean Academy of Nursing
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• v.33 no.1
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• pp.60-70
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• 2003

Purpose: The study is designed to develop an educational CD-Program for prevention and control of obesity among primary school students. Method: The study is conducted from June 15, 2000 to April 15, 2002. Based on the course of program development suggested by Dick and Cray (1990), the study followed the planning, development, education and evaluation of a program. Result: The developed CD-Program consists 2 parts each for lower and higher grades of primary school students. The introduction part of the first trial for lower grade students uses quiz to encourage their motivations, the body proceeds with motion pictures and animations to trigger their interests. The introduction part of the second trial for the lower grades consists of remembering the exhibition lecture. The first trial for higher grades of primary school students builds on the contents of the low grades. Its body part, how to determine obesity and calculate ones own obesity, puts ones own weight and height in by the mouse. For the second trial of the higher grades, the body consists of life-style, diet, and regiments. Conclusion: The merits of this CD-Program are that to be possible an interaction between teachers and students.

• Korean Journal of Childcare and Education
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• v.15 no.4
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• pp.21-36
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• 2019

Objective: Using data from the Panel Study on Korean Children, this study investigated the influence of teacher'thoughts about the transition from ECEC to primary school in relation to learner-centered teaching methods and children's school adjustment. Methods: We analyzed the longitudinal data of 658 seven-year-olds from the 8th and 9th waves of the panel study of Korean children collected by the Korea Institute of Child Care and Education in 2015 and 2016. The main analysis method was Structural Equation Modeling(SEM). Results: First, theachers' thoughts about the transition from ECEC to primary school was noteworthy. Second, the more concern a theacher' had about transition, the higher their learner-centered teaching method. Third, teacher' concern about transition influenced children's school adjustment. Fourth, a teacher's learner-centered teaching method mediated concern about children's transition and school adjustment in the first year and the second year. Conclusion/Implications: According to the results of this study, 1st grade teachers' concern about the transition from ECEC to primary school has been found to be predictors of children's school adjustment.

• Radiation Oncology Journal
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• v.31 no.4
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• pp.177-184
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• 2013

Purpose: The aim of this study was to analyze the patterns of care and treatment outcomes in patients with primary thyroid lymphoma (PTL) in a single institution. Materials and Methods: Medical records of 29 patients with PTL treated between April 1994 and February 2012 were retrospectively reviewed. Diagnosis was confirmed by biopsy (n = 17) or thyroidectomy (n = 12). Treatment modality and outcome were analyzed according to lymphoma grade. Results: The median follow-up was 43.2 months (range, 3.8 to 220.8 months). The median age at diagnosis was 57 years (range, 21 to 83 years) and 24 (82.8%) patients were female. Twenty-five (86.2%) patients had PTL with stage IEA and IIEA. There were 8 (27.6%) patients with mucosa-associated lymphoid tissue (MALT) lymphoma and the remaining patients had high-grade lymphoma. Patients were treated with surgery (n = 2), chemotherapy (n = 7), radiotherapy (n = 3) alone, or a combination of these methods (n = 17). Treatment modalities evolved over time and a combination of modalities was preferred, especially for the treatment of high-grade lymphoma in recent years. There was no death or relapse among MALT lymphoma patients. Among high-grade lymphoma patients, 5-year overall survival (OS) and 5-year progression-free survival (PFS) were 75.6% and 73.9%, respectively. Complete remission after initial treatment was the only significant prognostic factor for OS (p = 0.037) and PFS (p = 0.003). Conclusion: Patients with PTL showed a favorable outcome, especially with MALT lymphoma. Radiotherapy alone for MALT lymphoma and chemotherapy followed by radiotherapy for high-grade lymphoma can be effective treatment options for PTL.

• Journal of Gifted/Talented Education
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• v.20 no.3
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• pp.743-765
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• 2010

The purpose of this study was to provide and analyze the fundamental data on leadership skills and to analyze leadership skills among giftd elementary students according to grade, subject and gender. The main research questions in order to achieve the purpose of research are as follow. First, are there any differences of gifted elementary students' leadership skills in gifted groups? Second, do leadership program have an effect on improvement of gifted elementary students' leadership skills? The subjects for this study were 488 gifted elementary in 4th-6th grade in Busan. The students in the experiential group went thought 16 session do leadership program. After that, they had pre-tests and post-tests. the devices used to verify the effectiveness of the program were leadership skill scales. For this research analysis, MANOVA was used to investigate the first research questions and MANCOVA was used to investigate the second research question. Results from this study are as follows. Firstly, students in higher grades received fewer leadership skills points. This fact suggests that the leadership programs from the fourth grade should be implemented in 5th and 6th grade gifted education as well. Secondly, in the analysis of the results from gifted mathematics and gifted science, little significant statistical difference was shown. Thirdly, the analysis of leadership skills according to gender showed statistical significance. Finally, the study showed that the leadership education program had a positive effect. So the gifted 4th, 5th, and 6th grade students improve their leadership skills points by the end of the 16 week programs. Consequently, it is suggested that leadership education program on gifted elementary education was significant to improvement of leadership skills.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.1
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• pp.133-143
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• 2014

The purpose of this study was to examine the effect of scientific discussion classes focusing problem finding on the primary school students' scientific creative problem solving ability, science process skills and attitude toward science class. To verify this research problem, the subject of this study was fifth-grade students selected from four classes of M elementary school located in Busan city. For four months, the experimental group of 51 students was taught using the "scientific discussion classes focusing problem finding". The control group also of 53 students was taught in normal classes which used a text-book. All students were given pre and post test to verify the effects of scientific discussion classes focusing problem finding on the primary school students' scientific creative problem solving ability, science process skills and attitude toward science class. The results from this study are as the following. First, the scientific discussion classes focusing problem finding were effective in scientific creative problem solving ability among the primary school students. It is possibly because in the process where one student compare his/her own thoughts with the others' ones and discuss them. Second, the scientific discussion classes focusing problem finding were effective in science process skills among the primary school students. Third, the scientific discussion classes focusing problem finding were effective in attitude toward science class. In conclusion, the scientific discussion classes focusing problem finding had positive effects on improvement of primary school students' scientific creative problem solving ability, science process skills and also could lead to a change in students' cognition about science class to a positive way. Therefore, the scientific discussion class focusing problem finding is hopefully to be provided as an effective instructive strategy of science class in school in the future.

• Journal of the Korean Society of School Health
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• v.23 no.2
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• pp.217-227
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• 2010

Purpose: The purpose of this research is to enhance the effect of pictures on sexual education on primary school children which is one of the most crucial topics in health education and to evaluate how utilizing drawings can contribute to the development of school children's appropriate knowledge and attitude toward sexuality. Methods: This research followed the pre-test /post-test experimental and control group design. The selected school children of four classes at sixth grade in the H primary school in Gyeongi-do uijeongbu province had a pre-test about the knowledge and attitude toward sexuality. With the result of homogeneity data, three classes out of the four classes were chosen to be the subject of the post-test and these three groups took the "Sexual Education through Pictures." Results: After analyzing the data, average scores about the knowledge for class participants were higher than the non participants' (p =.000). Average scores about the knowledge of boys and girls who participated in class were higher than the non participants' (boys; p =.00, girls: p =.000). In addition, average scores about the attitude for class participants' were higher than the non participants' (p =.03), but there was not statistically significant among gender. Conclusion: From the results above, "Sexual Education through Pictures" proved to be a systematic and scientific method to develop a positive influence towards the knowledge and attitude of sexuality for primary school children of the sixth graders. These results show that the above teaching materials suggest an effective method to develop appropriate knowledge and attitude towards primary school children's sexual education.

• Tuberculosis and Respiratory Diseases
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• v.46 no.3
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• pp.426-431
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• 1999

The primary pulmonary lymphomas are uncommon, accounting for 0.5% of primary lung tumor and 0.4% of all malignant lymphomas. The majority of primary pulmonary lymphomas are of B-cell originating from bronchus associated lymphoid tissue(BALT). Angiocentric lymphoma is a rare type of primary pulmonary lymphomas characterized by polymorphic lymphoid infiltrates, which make it even more difficult to differentiate from benign infiltration. The radiographic findings are variable, depending on the stage of evolution of the disease. The prognosis of angiocentric lymphoma is poor, nearly two-thirds of the patients with grade 2 or 3 angiocentric lymphomas were died within a year of diagnosis. We report a case of primary pulmonary angiocentric lymphoma manifested as a mass of right lower lobe.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.1
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• pp.92-97
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• 2000

Osteosarcoma is a primary malignant tumor arising most often in the long bone, but rare in jaw bone. Especially osteogenic sarcoma of the mandible is a rare tumor, comprising less than 0.5% of all head and neck tumors. Osteosarcoma occurs chiefly in young persons, and presenting very survival rates. Histopathologically this tumor can be classified three types, osteoblastic, fibroblastic, chondroblastic and classified from low grade to high grade by anaplasia or mitosis of the tumor cells. Sometimes, the exact diagnosis of osteosarcoma is difficult especially in low grade osteosarcoma, even if clinical or radiographical findings suggest to osteosarcoma. So suspcious to malignant bone tumor in clinical or radiological findings, biopsy should be taked from deep portion and multiple area, and sharing the patient history and radiographs with pathologist will assist in the development of the diagnosis. We report a case of low grade osteosarcoma on the mandible initially difficulty in accurate diagnosis. The patient visited our hospital for routine dental treatment but radiographic findings displayed ill-defined radiolucency with osteoid formation on the mandible. Final diagnosis was difficulty in initial biopsy but subsequent biopsy taked from deep portion presented infiltrative growth and mitosis of the tumor cell in some area with small osteoid bone formation, so we could reach final diagnosis as low grade sarcoma. We treated this patient with bloc resection of the mandible and immediate reconstruction with iliac corticocancellous block.